Caffeine may undermine blood transfusion effectiveness

A new study has found that caffeine, the world's most consumed psychoactive substances, may impair the quality of donated blood and reduce the effectiveness of transfusions—especially in recipients whose red blood cell (RBC) metabolism is influenced by a common genetic variant. The REDS RBC-Omics study, which analyzed samples from over 13,000 blood donors, the study reveals higher levels of caffeine in the blood are linked to RBCs that are more prone to damage during storage and less effective after transfusion. In a clinical setting, transfusions of RBCs with relatively high levels of caffeine resulted in lower increases in patients' hemoglobin...